The invention relates to a multi-cylinder internal combustion engine and in particular, to means for making a selected number of the cylinders of the engine inoperative whereby to cause the engine to operate on less than all of its cylinders, and thusly change the operating characteristics and fuel consumption of the engine so that it will operate at a fraction of its power output and at a corresponding reduction in fuel consumption whenever full power is not required.
In the past, several inventions have been developed for inactivating a selected number of cylinders of an engine during different stages of its operation in order to reduce fuel consumption. One such device is illustrated in U.S. Pat. No. 2,197,529, wherein the inventor utilizes two inlet manifolds. Certain of the cylinders are connected to one manifold and the others to the other manifold. By arresting the flow of fuel into one of the manifolds, while delivery is continued to the other manifold, half of the cylinders of the engine are de-activated, thus resulting in a conservation of fuel; for instance, in an automobile that stops at frequent intervals while permitting the engine to run idly while the driver attends to some errands.
Another device for inactivating predetermined cylinders of an internal combustion engine is illustrated in U.S. Pat. No. 2,528,983. In this system, each of the intake and exhaust valves have a plurality of cams with which each may be brought into contact. Depending on which of these cams the bottom of the valve comes into contact with, determines whether the valve will open or not. These cams are moved by shifting the camshaft laterally to change the operation of the exhaust and intake valves.
A third system for de-activating predetermined cylinders of an internal combustion engine is illustrated in U.S. Pat. No. 2,948,274. In this device, the desired results are effected by locking the valve lifter mechanism of the exhaust valve of each said selected cylinder out of operation after the exhaust valve has been opened. Normal operation is resumed by releasing the locked valve lifters.
Numerous other attempts have been made to devise cylinder de-activator systems for internal combustion engines but most have not been successfully received by the public.
It is an object of the invention to provide a cylinder de-activator system that may be retrofitted to internal combustion engines presently in operation on the highways.
It is also an object of the invention to provide a novel cylinder de-activator system that may be installed on a typical internal combustion engine by changing as few parts as possible.
It is a further object of the invention to provide a novel cylinder de-activator system that can be adapted to a typical internal combustion engine by a do-it-yourself mechanic.
It is an additional object of the invention to provide a novel cylinder de-activator system that can de-activate any number of cylinders on a given engine by simply stopping the air/fuel flow and exhaust gas flow in that cylinder.
It is an additional object of the invention to provide a novel cylinder de-activator system which immobilizes the normal up and down reciprocal motion of the push rod.
It is an additional object of the invention to provide a novel cylinder de-activator system using a hydraulic method of de-activating the valves, thereby attaining a cushion effect which causes less mechanical shock on the the valve train than a strictly mechanical mechanism when reactivating the valve at high speeds.